DMM (distributed mobility management) emerges to resolve problems of conventional centralized mobility management such as a single point of failure and router redundancy.
Route optimization (RO) is a default feature of DMM, that is, a network supporting DMM performs route optimization automatically. FIG. 1 shows a scenario in which an MN (mobile node) and a destination node are mobile nodes. A home mobile router (indicated by 1 in FIG. 1) serving the MN allocates an HoA (home address) to the MN, and the MN is currently attached to a current mobile router (indicated by 2 in the figure) serving the MN. Likewise, 4 in FIG. 1 indicates a home mobile router serving the destination node, 3 in FIG. 1 indicates a current mobile router serving the destination node, and 5 in FIG. 1 indicates the MN, and 6 indicates the destination node. Because the MN is currently attached to the current mobile router serving the MN, the MN under the home mobile router serving the MN is marked with a dashed line. This also applies to the destination node.
When route optimization of DMM is not used, a data routing path between the MN and the destination node is shown by a dashed arrow in FIG. 1, where data coming from the MN is forwarded by the current mobile router serving the MN to the home mobile router serving the MN, then sent by the home mobile router serving the MN to the home mobile router serving the destination node, then forwarded by the home mobile router serving the destination node to the current mobile router serving the destination node, and finally forwarded to the destination node. As can be seen, the path is not optimized, a transmission delay is increased, and a single point of failure easily occurs.
After route optimization of DMM is used, through an optimized tunnel of DMM shown by a solid arrow in FIG. 1, data between the MN and the destination node may be directly sent by the current mobile router serving the MN to the current mobile router serving the destination node, and then forwarded to the destination node, where the optimized tunnel of DMM may be implemented by a protocol, such as GTP (General Data Transfer Platform), PMIP (Proxy Mobile IP), or GRE (Generic Routing Encapsulation).
In the network supporting DMM, route optimization is a default feature of DMM, and the network performs route optimization automatically. However, in some cases, it may be necessary to send data to a designated network node. In the prior art, without route optimization, data needs to pass through a relatively long and complicated path before arriving at an end point; or with route optimization, data is directly sent from a source node to a destination node, and cannot arrive at an intermediate network node. Evidently, in the prior art, an objective of sending data to a designated network node cannot be achieved.